EAST RUTHERFORD, N.J. - Antonio Pierce did not know Giants teammate Plaxico Burress was carrying a gun last weekend until it accidentally discharged, injuring the receiver in the right thigh, Pierce's attorney said yesterday.

"He had no idea Plaxico had a weapon," the linebacker's attorney, Michael Bachner, said in a telephone interview.

Bachner said Pierce would cooperate with authorities and testify before a Manhattan grand jury about the incident if asked to testify, which has yet to happen.

"Antonio has always taken a position that he will be cooperative in the investigation with law enforcement. . . . If he is [subpoenaed to testify], he is going to abide by his obligations as a citizen," Bachner said.

Pierce refused to discuss the shooting and its aftermath after practice yesterday, but insisted that he would not be distracted when he plays against the Eagles on Sunday.

"This Sunday is no different from last Sunday," said Pierce, who came into the media room right after practice in a sweat-soaked gray pullover. "It is no different from Week 1. It's no different from the Super Bowl game. It's no different from the first game I ever played football.

"When I get on the football field, my focus is winning the game, first and foremost, doing my job, and helping my team win. That's what I plan on doing on Sunday."

Although Pierce did take Burress to New York-Presbyterian Hospital/Weill Cornell Medical Center, as instructed by a Giants trainer, he did not try to cover it up by registering Burress under a false name, Bachner said.

"Other than bringing him to the hospital, he had no involvement in the administration process," he said.

Bachner said he could not comment on a report that Pierce took Burress' gun to his home and later gave it to the receiver's wife, Tiffany.

Giants spokesman Pat Hanlon acknowledged on Wednesday that Pierce called team trainer Ronnie Barnes after the shooting and that Barnes told Pierce to take the injured player to New York-Presbyterian.

Hanlon said yesterday that the Giants had alerted NFL security about the early-Saturday shooting at a Manhattan nightclub, saying the team left it to the league to notify police. The NFL said its security department did contact police.

But police say the NFL was not forthcoming about the shooting.

When Barnes arrived at the hospital, he asked to see Burress, by name, and was taken to the room where he was being treated. Barnes later learned that Burress had been issued a hospital ID bracelet with an alias, and Hanlon said neither Barnes nor the Giants had any involvement with the receiver's being admitted under a false name.

Dr. Josyann Abisaab has been suspended for not reporting Burress' gunshot injury, as required by law.

Abisaab, who is affiliated with the hospital and specializes in internal and emergency medicine, could not be reached for comment.

Police still want to interview the people at the hospital who treated Burress and did not report the shooting. Even if Burress used an alias, the hospital must report a gunshot wound regardless of whether it knows the patient's identity.

Burress has been charged with illegal weapons possession, a felony that requires a mandatory minimum of 31/2 years and a maximum of 15 years in prison if convicted. The Giants have suspended him for the rest of the season.

Authorities are trying to determine whether Pierce tried to cover up the shooting. Police say Pierce returned to New Jersey with Burress' gun in the glove compartment of his black Cadillac Escalade. Investigators have impounded the SUV to search it for any blood or gun residue.